Harmon Leslie wrestled for Oklahoma State University and was a two-time All American. He began his coaching career as a student coach at OSU while completing his degree. In 1958 he moved to Winfield, Kansas, where he coached one year. In 1959 he moved to Tulsa and became the wrestling coach at Nathan Hale High School. He continued to coach at Nathan Hale until 1985 when his team won the State Championship title. His lifetime coaching record is 93-46. He also officiated wrestling on the high school and collegiate level for 20 years. Leslie was named to the Tulsa Edison High School Wrestling Tournament Hall of Fame in 1977, and was named the Oklahoma High School Wrestling Coach of the year in 1985. He was also awarded the V.E. "Onions" Martin Award for outstanding service and the enrichment of amateur wrestling in Oklahoma.